Category “MigrantWatch summaries”

We are happy to announce that the MigrantWatch database has now crossed 30,000 reports of Indian migrants. The 30,000th report was of 50 Rosy Starlings from near Basni in Chhattisgarh. It was uploaded by veteran MigrantWatcher Mr Arun MK Bharos, pictured here.

In this section we explore species-wise break-up of observations on MigrantWatch for 2012-13 and compare them with the previous season’s patterns. (Note that the migration “season” is taken to begin on 1 July of one year and end on 30 June the next year.)

Top 20 species for 2012-13

Species

Records in2012-13

Common Sandpiper

368

Grey Wagtail

298

White Wagtail

267

Pied Cuckoo

267

Barn Swallow

254

Rosy Starling

245

Wood Sandpiper

236

Blyth’s Reed-warbler

219

Western Yellow Wagtail

206

Greenish Warbler

203

Green Sandpiper

187

Western Marsh Harrier

173

Northern Shoveler

157

Northern Pintail

138

Hume’s Leaf-warbler

132

Whiskered Tern

128

Garganey

127

Brown Shrike

126

Western Black-tailed Godwit

120

Common Greenshank

119

Boldface indicates species that also figured among the top 20 during the previous season (see table below)

Species

Records in 2011-12

Rosy Starling

239

Pied Cuckoo

170

Blyth’s Reed-warbler

122

Common Sandpiper

119

Barn Swallow

117

Greenish Warbler

112

Wood Sandpiper

95

Ashy Drongo

93

Grey Wagtail

90

Western Yellow Wagtail

85

White Wagtail

79

Western Marsh Harrier

77

Common Kestrel

75

Booted Warbler

75

Green Sandpiper

71

Northern Shoveler

69

Brown Shrike

66

Eurasian Golden Oriole

59

Common Redshank

56

Asian Paradise Flycatcher

55

Zone-wise top 5 species during 2012-13

The top 5 species were considered separately for each zone (see table below). A look at this list indicates that the most-observed species vary appreciably according to zone. As there are very few sightings from the Northeast and the Islands, these zones are excluded from comparison.

North

Northwest

Central

South

White Wagtail

Rosy Starling

Common Sandpiper

Barn Swallow

Grey Wagtail

Common Sandpiper

Pied Cuckoo

Common Sandpiper

Hume’s Leaf-warbler

Greater Flamingo

Western Yellow Wagtail

Wood Sandpiper

Greenish Warbler

Western Black-tailed Godwit

Grey Wagtail

Blyth’s Reed-warbler

Grey-headed C. Flycatcher

Northern Shoveler

White Wagtail

Brown Shrike

Half of all observations logged by MigrantWatchers in 2012-13 belong to 24 of the 265 species tracked by MigrantWatch. Interestingly, this number has remained nearly constant across the past five seasons (range 19-24). This suggests that there are some species that are either more popular, or are more abundant, or are easier to detect than other species.

This time we look at the arrival patterns of warblers. (Please note that each sighting is shown as a vertical black line.)

From the above illustration we can see that all the above four warbler species start arriving in early September. However, Blyth’s Reed-warbler appears to stay around the longest (until May). Booted Warbler leaves about a fortnight earlier than Blyth’s (mid-April), while Lesser Whitethroat and Hume’s Leaf-warbler stay only until the second half of March. These interesting patterns have only been revealed thanks to observations logged in by keen MigrantWatchers.

Here we look at number of sightings contributed and their geographical break-up for 2012-13 and compare these with the previous season’s figures. (Please note that the migration “season” is taken to begin on 1 July of one year and end on 30 June the next year.)

Number of sightings

During the 2012-13 season 9017 sightings were uploaded by MigrantWatchers, which was more than twice that of the previous season.

Zone-wise sightings during 2012-13

We have divided the country into very rough zones, as you can see below. In the 2012-13 season the Central zone accounted for most of the sightings, closely followed by the South. Although the NorthWest zone appears to lag behind, do note that this consists of only two large states, so actually is doing very well! Very few sightings came from the Northeast, and none at all from the Islands (Andaman & Nicobars, and Lakshadweep).

A marked difference from the previous season’s break-up was that Central zone overtook South in terms of the share of the sightings for 2012-13 (see below).

Zone-wise increase in sightings

All zones (except for Islands) showed an increase over the previous season’s sightings (see following chart). The Central zone recorded the highest increase in the number of reports (up 194% over previous season), followed by South and North. Although the number of reports is small, the trend for Northeast was positive (+44%) and we hope that many more sightings will pour in from this under-represented region in the coming seasons.

Top States 2012-13

Maharashtra, Karnataka and Gujarat returned the most number of sightings during 2012-13, followed by Madhya Pradesh and Uttarakhand (see table below).

State

Records in 2012-13

Maharashtra

2172

Karnataka

1851

Gujarat

1548

Madhya Pradesh

630

Uttarakhand

502

Haryana

355

Tamil Nadu

343

Delhi

272

Kerala

235

Chhattisgarh

228

For comparison, here are the details of the top 10 states during the previous season (2011-12).

Beginning with this post we present a series of articles that summarise the recently concluded MigrantWatch season (i.e. 2012-13), and compare it with previous seasons.

In this part we look at our contributors for 2012-13 and examine changes in contributors over the years. In all cases, we define a “season” as starting on 1 July of one year and ending on 30 June of the next year.

Number of contributors

As shown above, the last season saw contributions from 273 MigrantWatchers, which is an all-time high.

Top contributors for 2012-13

Contributor

Records

Shantilal Varu

1331

A Shivaprakash

894

Prathamesh Desai

656

Dipu Sasi

593

Pradnyavant Mane

559

Sachin Shurpali

318

Jayant Wadatkar

316

Ramit Singal

302

Arun M. K. Bharos

274

B R Sheshgiri

260

Number of new contributors

134 new people joined MigrantWatch and started contributing during the last season (see list below). The number of new entrants has been picking up in the last three seasons. (The number of new contributors in the first season is, of course, the total for that season!)

What percent of observers contribute 50% of all records?

During the past season half of all records were contributed by just 2% of the observers. (The proportion has more-or-less been maintained for the past three seasons.) This indicates that there is a very small number of MigrantWatchers that are exceptionally active. About 38% of contributors have uploaded a single sighting each, and this has varied slightly (i.e. between 32% and 41%) over the seasons. In the times to come we hope that we can motivate the not-so-active participants to contribute more regularly.

The following figure depicts the arrival patterns of Sandpipers and Common Redshank. (Note that each sighting is shown as a vertical black line.)

The above results show that the Common, Wood and Green Sandpipers, and the Common Redshank all begin arriving in July itself. The Green Sandpiper is the first to leave (early April) while the Common and Wood Sandpipers stick around until the beginning of May. Most Common Redshanks, too, have flown back by early May. Many thanks to all MigrantWatchers whose observations enabled us to come up with these summaries!

Our series on summaries of arrival patterns of our most-reported species continues here with results for Western Marsh Harrier, Ashy Drongo, Common Kestrel and Eurasian Golden Oriole. (Each sighting is shown as a vertical black line.)

As evident above, the Marsh Harrier arrives by September and is usually gone by April. Common Kestrel and Ashy Drongo come later in October and stay on till April. The Golden Oriole – an intra-subcontinental migrant – has observations spread over nearly the entire year. These summaries have been made possible because of your contributions!

In continuation with our presentation of present arrival patterns of our most-reported species, we now feature Black Redstart, Red-throated Flycatcher, Asian Paradise Flycatcher and Common Stonechat.

As in previous summaries each sighting is shown as a vertical black line.

It is apparent from the above chart that Black Redstart and Common Stonechat arrive in mid-September and generally leave by March-end. Red-throated Flycatchers arrive slightly in late September and return by April-end. The Paradise Flycatcher, which is an intra-subcontinental migrant, has records spread over the entire year. (Please note that this summary has only been possible thanks to your contributions!)

Does the arrival of the Pied Cuckoo herald the onset of the monsoon? The Pied Cuckoo Campaign was launched in 2009 to collect information to assess this age-old belief.

More than 600 sightings of this wonderful migrant have been contributed by over 200 MigrantWatchers so far; the first sighting dates among these were compared to monsoon arrival, as available with the Indian Meteorological Department (see the graph alongside). Each dot shows the earliest Pied Cuckoo report (after 1 May) for a broad location (an area roughly 200 Km across).

The results are fairly clear: Pied Cuckoos arrive before the monsoon in most parts of central and northern India (they are resident in southern India). You can see this from the pattern that most dots in the picture to the right are below the dotted horizontal line.

But the degree to which the arrival of the Pied Cuckoo precedes the monsoon varies from place to place, as can be seen from the scatter of the dots within each year. And even for the same general location, this varies from year to year (see how the coloured dots are in different places in different years).

What appears to be happening is that, where the monsoon arrives early, Pied Cuckoos arrive a few days before monsoon onset; but where the monsoon arrives late, the cuckoos arrive well in advance of monsoon onset.

So, overall, the old belief is true, and Pied Cuckoos tend to arrive before the monsoon — but to different degrees, depending on when the monsoon begins at each place.

Since 2007 MigrantWatch has brought together hundreds of birders across India to pool their observations of migratory birds. Over the years, our enthusiastic participants have collectively contributed more than 20,000 records of nearly 250 bird species. The idea of collecting all this information in one place is to document patterns of bird migration in the Indian subcontinent.

To mark the completion of 5 years of MigrantWatch, we have put together a brief summary of the migration patterns that are emerging. We hope you will enjoy it, and will tell your other birding friends about it too.